1. Field of the Invention
The present invention relates to vehicular drive control systems. Particularly, it is concerned with vehicular drive control systems capable of preventing excessive drive wheel slippage occurring when a vehicle begins moving and during acceleration to ensure stable vehicular running and improve acceleration.
2. Description of the Prior Art
Heretofore, drive control systems have been known, such as those disclosed in U.S. Pat. Nos. 4,416,347 to Bartling et al and 4,484,280 to Brugger et al. In these known systems, however, in order to achieve so-called traction control, a special hydraulic pump is used, independent of the vehicle brake master cylinder, to pressurize a wheel cylinder to accomplish braking.
Since it is necessary to provide a separate hydraulic pump, the system structure becomes more complicated and more space is required, thus resulting in an increase in weight and manufacturing cost.